Which of the following italicized parts is a predicative clause（表语从句)？A．I have no idea

Which of the following italicized parts is a predicative clause(表语从句)？

A．I have no idea when he will leave for Britain.

B．It is very likely that they will hold a meeting.

C．The news that I have passed the exam is true.

D．The problem is when we can get a pay rise.

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